We have considered the phase behavior of sphere-forming block copolymers in confinement by means of dynamic density functional theory (DDFT) We have in particular focused oil the role oft he chain architecture by choosing two equivalent AB and ABA block copolymers The role of surface fields (epsilon(M)) and film thickness (H) oil the phase behavior is elucidated I-or both systems, we identified surface reconstructions Such its a wetting layer, parallel cylinders, perforated lamellae and lamellae, that were previously also Found in confined cylinder-formint, systems In contrast to cylinder-forming systems, we observed that the part of the film that is affected by the surface field depends on the nature of the surface layer In particular, cylindrical and lamellar Surface reconstructions Connect to the bulk structure in the interior of the film via cylindrical layers. The origin of this extended surface field range lies in the restricted chain conformations. As I direct consequence, confinement plays a role also in relatively thick films for stronger surface fields We show in detail the complex interplay between the surface field and confinement, and how this introduces it certain amount of asymmetry even for this setup with symmetric wetting conditions We Identified the role of the chain architecture, which is only striking in "neutral" surfaces, where a small repulsive interaction balances the entropic gain of positioning the shortest block next to the Surface The AB diblock forms a layered spheres structure for most H, while for the ABA triblock a new structure, perpendicular cylinders that span the film, is observed For all considered H